Produced by bacteria and some fungi, in response to extracellular signals, antibiotics represent a diverse group of compounds that inhibit bacterial growth at different points and different stages of the life cycle.

We will get around to antibiotic resistance, but in these few words, I think I already wrote quite a bit. Admittedly, some of these ideas need a bit of chewing, if they are to be properly digested. Already, I can imagine hands raised and questions waiting to be asked.What are antibiotics made of?
I’m confused about this idea of biological warfare. Why would bacteria make substances that can kill other bacteria?

You said bacteria make antibiotics! Don’t we use antibiotics to kill bacteria?

Bacteria (and a few fungi) make antibiotics. In other words, they are natural products; just as natural as ginseng, digitalis, and golden seal.

But who makes them?

Bacteria make them – more later, and they bear a strong physical resemblance to the fungi that make antibiotics.

Do they exchange DNA? Do they represent some odd branch of the phylogenetic tree?

What do these compounds do that inhibits bacterial growth? What do they kill and how do they do it?
How can bacteria make antibiotics if antibiotics inhibit bacterial growth? Isn’t this some kind of microbial suicide?

Re: antibiotic resistance – now this is one of my very favorite subjects!* Were these questions put forward in a biotech class? If I recall correctly, you’re teaching in such a course, right? In any event, nice part 1 primer and I’m looking forward to part 2.

To be honest, these are questions that interest me. I probably will use them as assignments in future classes, though. I’m teaching a continuing ed course on bioinformatics for Shoreline Community College in January and some of these should be good research topics.